Real-time Continuous Glucose Monitoring in Infants With Hypoxic-ischaemic Encephalopathy: a Pilot Randomized Controlled Trial

Neonatal hypoglycaemia and hyperglycaemia are associated with brain injury and impaired neurodevelopment outcomes in neonates with HIE. Improving early glucose control is an important modifiable risk factor for outcomes in this population. Glycaemic monitoring is usually performed by capillary or central line sampling. However, over 30% of the episodes of abnormal glucose concentration are undetected, even with regular but intermittent sampling. CGM can allow earlier detection and prevention of exposure to extreme glucose concentrations.

Study design - This is a multicentre interventional, open-label, randomized controlled trial of CGM compared with standard clinical management (control).A total of 70 neonates (Birth weight >1.8kg, Gestation >36 weeks and aged <6hours) with moderate or severe HIE following perinatal asphyxia will be recruited within 6 hours of birth after informed parental consent. Neonates with major congenital malformations, inborn errors of metabolism, congenital infections, imminent death will be excluded.

Neonates will be randomly assigned (1:1) to receive either the intervention with real-time CGM for 72 hours or standard care using a randomization program (R package SRS: A Subject Randomization System). We will use the minimization method to control for severity and to achieve balance within recruiting centres. In all the neonates recruited Dexcom ONE+ CGM (Dexcom, San Diego, CA, USA) will be placed soon after study enrollment. The sensors will be inserted in the lateral thigh and continuous measurements will be recorded for 72 h. The CGM device will be calibrated using blood glucose values measured by point-of-care test. CGM calibrations will be performed at least twice a day. CGM data will be downloaded by using Dexcom Studio software on a dedicated computer.

In the standard care group, the CGM device will collect glucose data continuously, but the clinical team will be blinded to the data. These neonates will have their glucose control monitored and managed according to standard clinical practice using intermittently sampled blood glucose levels. In the intervention group the CGM data will be used to support clinical management including blood glucose measurements and decision making. Changes in glucose and insulin infusion will be based primarily on the real-time CGM data but blood glucose concentrations will be checked in case of rapid changes in CGM data.

Interventions to target glucose control will be guided by a protocol shared among the participating hospitals. As part of the study protocol, all the neonates will receive a continuous infusion of glucose 10% of 3-4 mg/kg/minute and total fluid intake starting at 50-60 ml/kg/day followed by titration depending on urine output, renal function, and management of glucose infusion rates.